Former Nigerian President Olusegun Obasanjo, the United Nations special envoy for eastern Congo, met Congolese President Joseph Kabila late on Friday and will fly east for talks with rebel leader Laurent Nkunda.
Obasanjo is trying to avert a broader regional war breaking out after battles between Nkunda's Tutsi guerrillas and the Congolese army forced some 250,000 people from their homes in Democratic Republic of Congo's North Kivu province.
"They met last night," a source in the DRC presidency told Reuters. "(Obasanjo) is now due to go to the east to find out what it is Nkunda wants and tell him this is his last chance."
No details of the meeting in Kinshasa were available.
Obasanjo, who was named last week by U.N. Secretary-General Ban Ki-moon as his special envoy, met Angolan President Jose Eduardo dos Santos in Luanda before flying to the Congolese capital, and has already spoken to Nkunda by telephone.
The United Nations says the fighting has triggered a humanitarian catastrophe. On Friday, aid workers began feeding tens of thousands of refugees in rebel-held areas.
There are fears the violence could escalate into a repeat of a 1998-2003 war that sucked in the militaries of six African states and led to millions of deaths.
Kabila accuses neighbouring Rwanda of supporting Nkunda, while southern African states led by Angola have said they are considering sending troops to back the Congolese army, or to bolster a stretched 17,000-strong U.N. force in Congo.
The origins of the conflict can be traced back to Rwanda's 1994 genocide of Tutsis by Hutus, which helped trigger the 1998-2003 war. Kinshasa accuses Rwanda of backing Nkunda, who says he is defending Congolese Tutsis from attacks by FDLR Rwandan Hutu rebels he says fight with the Congolese army.
The BBC said late on Friday that the Congolese and Rwandan foreign ministers, Alexis Thambwe Mwamba and Rosemary Museminali, had agreed in the Rwandan capital Kigali on moves to try to end the conflict on their border.